​ATLANTA -- After learning that he would realize his dream to pitch in the big leagues, Braves right-hander Aaron Blair flew from Charlotte to Atlanta on Saturday morning and arrived at Turner Field a short time later, only to be told that he would need to experience his final hours of anticipation away from the stadium.

When Blair returned on Sunday morning to get his first true taste of being a big leaguer, he took advantage of the chance to show why he stands as a highly-regarded prospect. But the damage he incurred at the start and end of his debut proved costly enough for the Braves in a 3-2 loss to the Mets.

"It was good to get out there to make my debut," said Blair, who ranks as the No. 54 overall prospect by MLBPipeline.com. "You only make it once. It was a special day for me and my family."

As his parents, fiancée and approximately 20 other friends and family members settled into their seats, Blair encountered immediate trouble, surrendering a single to three of the first five batters he faced. Michael Conforto's sacrifice fly gave the Mets a first-inning lead and also accounted for the first out recorded by the promising 23-year-old, who seemed unfazed by his rocky beginning.

"I actually wasn't too hyped or too anxious, especially after the third pitch, giving up a base hit and then fifth pitch, base hit," Blair said. "I kind of had to settle in real quick and it was fun."

Blair's fastball gained a little more life in the second inning and he benefited from a couple double-play groundouts that helped keep the Mets scoreless until the sixth inning. Curtis Granderson drew a one-out walk in the sixth and Asdrubal Cabrera followed with a single before Blair's debut concluded with an elevated changeup that Conforto bounced over the right-center-field wall for a go-ahead double.

While manager Fredi Gonzalez felt Blair tired in the sixth, veteran catcher A.J. Pierzynskifelt the young pitcher lost the aggressiveness he had possessed while limiting the Mets to just one hit from the start of the third inning through the end of the fifth.

"I wouldn't say I got tired," said Blair, who was charged with three runs and six hits over 5 1/3 innings. "I'd just say fastball command got away from me."

This has been a whirlwind week for Blair, who cemented his candidacy to replace Williams Perez in Atlanta's rotation when he tossed seven hitless innings against Durham on Tuesday. Blair got the sense that he would make his debut on Thursday, when Triple-A Gwinnett pushed Mike Foltynewicz's start back a day until Sunday, which is when Blair would have been scheduled to next pitch for the G-Braves.

Blair has been on a fast track to join the Braves since early December, when he was included in the blockbuster trade that sent Shelby Miller to the D-backs. He impressed during each of the three starts he made for Gwinnett this year and now, he'll have a chance to prove he is capable of taking the ball once every five days for Atlanta for a long time.

But regardless of what transpires over the next few years, Blair will never again experience the thrill of running out of the dugout to realize that childhood dream of becoming a big league pitcher.​"It's something I'll never forget," Blair said. "I'm truly blessed to have had the opportunity."